Primary drive and clutch

The primary drives and clutches of both the Twins and Triples are effectively the same although there are some disassembly and assembly differences mostly concerning other components.

Before starting any work on the primary drive and/or clutch, you must drain the engine oil and slacken right off the primary chain adjuster. This is discussed in the Maintenance section.

On the Twin, remove the contact points cover and dismantle and remove the 'ignition system' as described in the Electrical and Ignition section. (Late SFCs use a trigger system also described]. With the contact points plate and advance/retard mechanism removed, you can now start tackling the primary drive cover.

Proceed for both the Twin and Triple as follows. Undo and remove each of the primary drive cover setscrews. Retain the washers and note.where the long and short screws fit on the Triple. The cover will be stuck to the crankcase. Don't lever it off even though the factory provide you with two flats on which to do so. Instead, gently hit with glancing blows all around its periphery with a hide-headed hammer. Sooner or later it will free itself. (If the engine is still in the frame, undo all the bolts, slacken the primary chain tensioner and operate the starter motor. The cover will come off instantly.) Once it is free, carefully pull it off the crankcase square for it has two needle bearings fitted in it. Remember to catch and mop the oil residue which will spill as it frees. Remove the gasket and clean up the face at this stage. Methylated spirits and a sharp knife should help you remove the gunge.

At this stage there are visible differences between the Twin and Triple. They concern the Twin's oil pump drive which comes off the crankshaft via two gears. The pump drive gear (that's the big gear sitting hiding the oil pump) should pull out if the correct procedure is followed. It's held in its correct position by a peg which passes through its shaft.

Now to proceed (on both models), you must lock the primary drive so that you can undo the crankshaft nut once its locking washer has been bent back. If the engine is still in the frame, then you can engage fifth gear, press on the rear brake pedal and hold the engine that way. With the engine out of the frame, Laverda recommend you use their special tool. Strickly though, it's not necessary. You can easily make up a small metal bar (it must be strong) with which you can chock the crankshaft and clutch sprockets. The bar needs to be about 3 inches long and must be the full width of the sprockets, about lVz inches. See the photograph.

With the engine held by an assistant, use a socket to undo that crankshaft nut. Remove the nut and locking washer. On the Twin, now remove the oil pump drive gear mounted on the crankshaft: before you pull off the oil pump driven gear check that it has the proper markings visible so that you can refit it all correctly. If these marks are not there, then you must make your own. There should be a mark ('point') on the crankshaft cutaway. A mark ('line ) on the crankshaft-fitted oil pump gear should align with a mark ('line') on the oil pump driven gear (/contact breaker drive).

Now be careful with the procedure to be followed for the oil pump driven gear removal. The internal oil pump driven gear is keyed onto the oil pump driven shaft by a cylindrical peg which is perpendicular to the shaft. In order to pull out the gear, this peg must be in front of the cutaway in the oil pump body. A mark is made on the oil pump driven gear which shows the position of the peg on its shaft.

Rotate the oil pump driven gear so that the mark is pointing forward, i.e. at 9 o'clock, then pull the gear out. If it won't come, don't force it, but turn the oil pump driven gear through 180° so that the mark is at 3 o'clock. In one or other of these positions the oil pump driven gear can be pulled out. Remember that you are doing all this seemingly complicated work not for the sake of the oil pump but because you want to be able to ensure that your ignition contact breaker timing is going to be spot-on when you reassemble. The oil pump drive also drives the contact breakers.

Now remove the primary chain tensioner. It slides onto a removable peg. At this point the primary drive is free at the crankshaft but not yet at the clutch. To free the 'back to front' clutch drum release the circlip and shim behind it with a pair of circlip pliers. Now with both hands pull off, together, the crankshaft primary drive sprocket and the clutch drum with the primary chain connecting each. Place that on the bench and then remove and note the position of the shims in front of and behind the clutch drum.

At this stage you should make an inspection of three components. First check out the primary chain tensioner. Some early Twin tensioners used a wheel fixed by a circlip. Later ones use a blade method. If the wheel or blade is badly grooved, then it should be replaced and you should remember not to tension it so hard next time. The wheel/blade will not wear out at the same time as the primary chain. Check that its circlip or spring clip is intact.

Laverda recommend that the primary chain is changed very regularly — see the Maintenance section. The factory are playing safe, which is wise, but these chains have been known to go on for upwards of 20,000 miles without undue wear. However, triplex chains are not expensive and it makes good sense to replace them in good time.

The clutch drum is fitted with a cush-drive. Depending on use, the cush-drives will last upwards of 30,000 miles. Nevertheless it is easy to ascertain whether they are worn or not. If worn, they will be slack and loose and noise may have been forthcoming. Their replacement is fairly easy. It is necessary to grind off the rive? heads, (late Triples use small bolts), take off the outer cover, the sprocket and then the rub :>er bushes. New bushes and rivets are available as spares. Certain types of tiny, strong nuts and bolts could be used instead.

Also in the centre of the clutch drum is a bush on the Twin and needle bearing on the Triple, both of which normally take a long time to wear. If you have your doubts and there appears to be some scoring or shininess then measure the bush's bore, as per the Specifications, and if necessary replace it. Replace the needle bearing complete if roughness is experienced. If you warm the clutch drum in boiling water you should be able to drive out the old bush or needle bearing and drive in

Rest Chain Tensioner Tool

This is a Triple's primary cover being removec could not see the rest of the crankcase you col by the primary chain tensioner

The official factory tool is being used here to hold the crankshaft while the large nut on the crank is being undone

Laverda Clutch
It is possible to manufacture your own special tool to The pivot pin of the Twin's primary chain adjuster do the job. Here is a suitable example in use (Twin)

This is a Triple's primary cover being removec could not see the rest of the crankcase you col by the primary chain tensioner

The official factory tool is being used here to hold the crankshaft while the large nut on the crank is being undone

Crankshaft With Clutch Motorcycle

The standard clutch - in this case its a late type Twin clutch with screw fixing rather than the earlier peg. The Triple clutch is very similar

A screwdriver is the best tool, use when attaching the cable

The early peg type Twin clutch fixing components the new. (You could freeze the new one; that will help). Further clutch dismantling is, of course, quite possible. If you have experienced clutch slip then you must inspect the clutch plates and springs. Low mileage clutch slip, apart from clutch cable tightness, could be due to glazed plates (which should be roughened up with medium coarse emery cloth) while high mileage clutch slip could be due to weak springs and worn plates. At any stage, however, it makes good sense to replace the springs because they are so cheap To remove the clutch plates undo the six bolts on the pressure plate. (On early Twins, securing pegs were used instead. A Laverda tool was recommended for this although this appears :c be no longer available. Make up a tool using 8mm internal diameter tubing which has two 'diametrically cutaways at one end to allow the clutch peg to pass through). Undo the bolts progress:, el v and evenly. Once all are released, pull off the pressure plate and all other friction plates Still sitting in the primary drive casing is the clutch back plate held onto the gearbox primary shaft by the clutch actuation key, shim and circlip. The peg pulls out, the shim slides off; the circlip can be removed with circlip pliers. (On peg clutches, the back plate uses removable clutch spring posts. These are held in with a circlip). The clutch actuation mechanism consists of a rod which is split in the middle which runs down the centre of the primary shaft in the gearbox. In between :ce split in its centre is a ball bearing — there is also another at its far end, onto which the cabie-le er-arm presses when the clutch cable is 'pulled in'. It may be possible to pull out the split rod coth ball bearings from the centre of the primary shaft, although you will almost certainly ha^e to shake the crankcase first. The cable-lever-arm is under cover, the other side of the engine and s easily removed once the two gearbox covers are off.

The crankshaft nut is off and the clutch shafr I : is being removed

The clutch drum is off and one of the clutch plate fixing screws is being identified half out. Note the shim on the clutch shaft

Here are the clutch plates behind the drum and end cover

Once the clutch is reassembled but before the primary chain is installed you should check the 'parallel' of the twin chain sprockets. Note the shims on the clutch shaft

The crankshaft nut is off and the clutch shafr I : is being removed

The clutch drum is off and one of the clutch plate fixing screws is being identified half out. Note the shim on the clutch shaft

Here are the clutch plates behind the drum and end cover

Once the clutch is reassembled but before the primary chain is installed you should check the 'parallel' of the twin chain sprockets. Note the shims on the clutch shaft

Reassembly is basically a reversal of the disassembly procedure. You must inspect the following if you have not already done so.

Clutch plates — glaze, scratching, thickness, flatness and breakages Clutch springs — renew them if in any doubt Clutch actuation rod and ball bearings — straightness and wear Clutch back plate — lateral wear on its spline. If loose, replace Pressure disc — must be very smooth and perfectly shiny

Needle bearings in the outer primary cover — standard check for all needle bearings.

(Replacement is straightforward provided you heat the cover in boiling water first.

Bearing alignment is most important) Primary chain — standard chain wear test. Replace at 15,000 miles away When replacing the clutch, make sure all the shims are in the right place

Behind the clutch back plate is an O-ring. Replace the actuation rod and ball bearings, shims, a circlip and key.

Replace each plate onto the clutch back plate. Start with a friction plate and finish with a friction plate, soak each one in oil first. Now fit the pressure plate but at this stage only lightly do up ONE bolt (peg). By eye, line up the teeth of the friction plates and then gently push on the clutch drum to accurately align them. Take off the clutch drum and replace the remaining bolts, springs and washers (pegs). Tighten each bolt progressively and evenly. Before refitting the primary chain and its two sprockets, offer up both sprockets first, without the chain, once you have replaced the shims in their appropriate place. Check the sprockets for alignment with a good steel straight edge for it is essential that they align exactly, to ensure quiet running and long chain life. Swop shims, front to back and vice versa on the clutch drum if they don't align. Remove the sprockets and then offer up the two again but this time with the chain duly assembled.

Replace the shims and circlip (renew as necessary) on the primary shaft and refit the nut and locking washer with some Loctite, too, on the crankshaft. Tighten the nut. Lock the washer. On the Twin refit the oil pump driven gears, checking the alignment marks. For further oil pump information read the next sub-section.

Replace the primary chain tensioner on the Twin, with its chamfered spindle facing outwards. Do not tension the chain yet. Oil the primary chain and tensioner and then wipe away any excess. (The Triple's chain tensioner is in the cover).

Use a new gasket on the cover and carefully offer it up. Oil the needle bearings in the cover and then carefully push the cover on. Lightly do up four fixing setscrews around the cover and then carefully tap the cover home — two pegs in the cover have to align with the crankcase. Do NOT fit the cover by pulling it to on the setscrews. Install the rest of the fixing screws and do them up progressively to ensure an oil tight seal. Use gasket cement on the cover sparingly.

The arrow shows the clutch plates throwout peg before the clutch drum is replaced

The finger points to the two marks on the gear wheels - these must align (Twin)

The arrow shows the clutch plates throwout peg before the clutch drum is replaced

The finger points to the two marks on the gear wheels - these must align (Twin)

Clutch Plate For Laverda

J There's one of the ball bearings in the clutch release shaft mechanism. This one is at the cable end of the shaft (the cover is removed for photography)

2 The clutch master cylinder mounted on the handlebar

3 The clutch slave cylinder hides behind the gearbox cover. The bleed nipple cover and rubber bung have been removed for this shot

On the Twin, replace the contact breaker and advance/retard mechanism. Tune the engine. Run the engine and tension the primary chain. Check the work of the clutch. Vibration and noise may be caused by any number of incorrect fittings. If you are sure it is not caused by an incorrectly tensioned primary chain, check the tightness of the crankshaft sprocket (if lose, it knocks loudly) and the shimming of the clutch drum and back plate once you have removed the cover again. (When renewing sprockets on the very early Twins with later replacement parts, particularly crankshaft sprockets, make sure that they can be tightened properly. If this proves to be impossible, then you must shim up until looseness disappears).

Primary chain tensioning appears in the Maintenance section, as does clutch adjustment.

The hydraulic clutch is no great mystery although the Laverda 1200 is the first modern production motorcycle to be so fitted. The master cylinder on the left hand side of the handlebars is a conventional brake-type master cylinder. For its servicing read the Brake Chapter. The slave cylinder at the gearbox end is a conventional car-type slave cylinder which hides in and behind the cover of the gearbox. The hydraulic hose which connects master cylinder with slave cylinder is thoroughly conventional too.

Hydraulic fluid bleeding is undertaken ¿sing a similar method to that described for disc brakes in the Brake Chapter. The clutch slave cylinder bleed nipple is found on the outer gearbox cover.

To reach the slave cylinder it will be necessary to remove the outer gearbox covers, although the hydraulic hose could be replaced by removing the rubber bung and undoing the hose from the outside. Once the inner of the two gearbox covers is removed theslave cylinder can be dismantled in a conventional manner, similar to the one used for the brake master cylinder.

Badly functioning hydraulic clutches will suggest poor gearchanging and clutch slipping. It should be a reliable unit.

J There's one of the ball bearings in the clutch release shaft mechanism. This one is at the cable end of the shaft (the cover is removed for photography)

2 The clutch master cylinder mounted on the handlebar

3 The clutch slave cylinder hides behind the gearbox cover. The bleed nipple cover and rubber bung have been removed for this shot

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